Additive manufacturing (AM), also known as solid freeform manufacturing or rapid prototyping, is a class of manufacturing techniques in which successive material layers are stacked over one another to produce three-dimensional objects. Additive manufacturing boasts several advantages over conventional subtractive manufacturing, including the ability to create highly complicated geometric shapes, greatly improved material efficiency, and compatibility with a broad range of materials and applications. However, the layer-by-layer approach of most additive manufacturing processes has drawbacks, including relatively poor inter-layer bonding and induced anisotropy in the manufactured object. Considerable research and innovation have been directed towards compensating for these shortcomings, which has led to the development of several multiple-axis additive manufacturing processes and post-fabrication treatments for three-dimensional objects.